Aryl ethers



Patented Mar. 22, 1949 UNITE-D STATES ARYL ETHERIS 'Moushy jMarkarian,

\ Mass, a corporation of No Drawing. Application;Mayal8sl94fi, Serial No. 6}igQ;85,5

r, tutedoni-aniaryl: group.

Diphenyl ether :and number :ofsimple .de-

rivatives thereof, rhavewbeenpknown :and-iwidely used fora number =of years. In certainapplicavtionsthey have beenmunsatisfactory because .of

their :electrical, chemical -or physical properties.

"It'is an ob'jectof thezpresent invention -to pro.-

duce new diaryl ethers. A/further object :is to produce new diaryl ethers-with at leastone trifluoromethyl groupasubstituted .on an .aryl group.

A still further object is to produce-new diphenyl ether compounds useful for a Wide range of purposes. Additional objects will become apparent from a consideration of thefollowingdescription and claims.

These objects are attained in accordance with the present invention'wherein there are produoed compoundsconforming .to the following general formula:

wherein it represents an arylgrou p, which may be further substituted, and n represents the integer l, 2, 3, 4, or5.

In a more restricted sense this invention is con cerned with compounds conforming to the follow- .ing general formula:

wherein R represents an aryl'group which may be further substituted.

In a still more restricted sense this invention is concerned with compounds conforming to the following specific formula:

wherein X represents a substituent selected from the class containing halogens (particularly chlorine and fluorine) and alkyl groups-and n represents the integer l, 2 or 3. The invention is also concerned with methods of making the above compounds and is specifically concerned witha proceess comprising reactingmetabromo benzotrifluoride with alkaline salts of hydroxy aryl compounds such as phenol and -ring-substituted phenols.

We have discovered thatdiarybethers having useful electrical, chemicaland physical properties may be prepared by simple means. Among the preferredcompounds. of: theinvention are :the following:

North Adams, and -,Dav id "B. Peck, Williamstown, .M ass,, Sprague Electric -,0

its-signer t North Adams,

Massachusetts .2 3-.trifiuqrnmethy iph nyhethe r2atr fluqmmethrldipheny e :L-trifluoromethyl diphenylether 3-trifluoromethyl-4-ch10ro diphenyl ether 3-trifluoromethyl-i2fiqchloroidiphenyl ether 3-trifluoromethyl-Bhflhloro diphenyl ether Z-trifiuoromethyl-2-chloro diphenyl ether 2-trifiuoromethyl-3'-chloro diphenyl ether Z-trifluommethsd-fl:fiach o o d hen l ethe -trifiuoromethyl zfi chloro,diphenyl ether 4-trifiuoromethyl-3'-chloro diphenyl ether AitlifiuoromEthyl-l-ch10r0 diphenyl ether i3= trifluoromethy1= 2f-;4' dichloro diphenyl ether ;3 trifluoromethyl-2,5-dichloro diphenyl ether 13-trifluoromethylphen-yl--l naphthyl ether 3-trifiuoromethyl-3"ethyl diphenyl ether Iifil1Q1"Qm 11h,y 'i 'sd fi hy diphenyl et r in-addition to -the above compounds a snide variety of related "materials may be obtained, in --acco-rdance with our invention. "It is contem- ;p1ated that diaryl ethers having a tri-fluoro =methyl-groupon each aryl ring may be prepared. "It is fu-rther --contemplated that polyaryl cyclo polyethers may 'be obtained Joy reacting alkaline salts of metaghalqgen substituted phenols, which may be further substituted, v in the presence of copper or copper salts. The products thus obtained would have -a-=structure with four aryl rin s wan -f il!.mi e n c uplin leme If alkaline salts ,ofmara halqgensubstituted phenols are reacted in the presence of copper or its salts, useful compounds are obtained which probably :are polyaryl ethers offllinearnature. -'We'-'have foun-d that aryl substitution-by one or: -m0re-triifluoromethyl'groups will enhance appreciably-thev desirable properties of "the --resulting product, withou decr a n it ioh m al stabili y. T r actions.imentionedsabor may ,be c mbmed :t prod c iise ihie imcl sula ew iehtep yary ethers.

The following examples, wherein the uantities are stated in parts by weight,-will serve to illustrate the meansof obtaining the novel compounds of the invention.

:iEXAMPLE 11 Preparation ofd-trifluoromethyl diphenyl ether h t-t (,Lmole) m-bromo benzotrifluoride .(B..,P.,

,-151-152 C.) 225 Phenol (1.25 moles) loose crystals M. P..4,1',C. .LLB KOH (1 mole) pellets 56 hegnh npliand QHN EB, a eddn a3 necke flask equipped with an oil sealed stirrer, ,reflu,x condenser with take on? adapter, and a thermometer, and heated;.wi-thetirringiuntil all KOH had dissolved. The copper :ROWfifiI was then added,

and then the m-bromo benzotrifiuoride. The mixture was heated with stirring until H and the m-bromo mixture began to reflux. The Water Was continuously separated and the m-bromo compound returned to the reaction. The rate of reflux gradually decreased as the reaction took place with separation of KBr until finally a temperature of 180-190 C. was reached (approximately 3 hours). The mixture was kept at 180- 190 C. for another 2 hours, then cooled and poured into 1000 parts of water containing parts NaOH. This was then steam distilled. The steam distillate consisting of the diphenyl ether and unchanged m-bromo compound was then separated from the water, washed with dilute NaOH, dried with MgSO4, and fractionated, Recovered 25 parts m-bromobenzotrifiuoride. Yield of etherl84 parts, boiling point '7375 C./1 mm.

R. I. 20 C.=1.5118 d20/4=1.240

EXAMPLE 2 Preparation of 3-trzfluoromethylphenyl lnaphthyl ether Parts m-Bromo benzotrifiuoride 232 Alpha-naphthol (B. P. 135-137 C./'7 mm.) 240 KOH Cu powder 1 R. I. 20 C.=1.5'784 d20/4=1.2629

EXAMPLE 3 I Preparation of 3-tr2'fluoromethyZ-4'- chlorodz'phenyl ether Parts m-Bromo benzotrifluoride 168.75 p-Chlorophenol (M. P. 3940 C.) 120.75 KOH 42 Cu powder The procedure of Example 1 was followed, giving a recovery of the bromo compound of 39 parts. Yield of ether parts, boiling point 93-95 C./1 mm.

R. I. 20 C.=1.5278 d20/4=1.3336

EXAMPLE 4 Preparation of 3-trz'fluoromethyZ-3'- ethyl diphenyl ether v Parts m-Bromobenzotrifluoride 118 m-Ethyl phenol 64 KOH pellets 29.4 Cu powder .5

The procedure of Example 1 was followed, with .a recovery of 10 parts of the m-bromo compound. Yield of ether-106 parts, boiling point 89 C./1 mm.

R. I. 20" c.=1.51oo d20/4=1.180

EXAMPLE 5 Preparation of 2,4-dimethyZ-3-trifluoromethyl diphenyl ether The procedure of Example 1 was followed, with a recovery of 20 parts of the unreacted m-bromo lea compound. Yield of ether parts, boiling point 9192 C./1 mm.

R. I. 20 C.='1.5113 d20/4=1.182

In the same manner, other aryl ethers with trifluoromethyl groups on one or more of the aryl groups may be prepared. Triaryl diethers may also be prepared by a suitable adaptation of the above method. Dihydroxy benzene compounds such as hydroquinone may be reacted with two moles of a bromo benzene, preferably also sub- 1 stituted with a trifiuoro methyl group. Alternately, dibromobenzene may be reacted with the alkaline salt of phenol. By either method three phenyl groups would be interconnected by two oxygen atoms.

The electrical properties of the compounds of this invention are such that they may be employed in electrical condensers and for other dielectric purposes. For example, B-trifluoromethyl-3-ethyl diphenyl ether has a dielectric constant of 7.4 and a 1,000 cycle power factor of 013% at 26 C.; and 3-trifiuoromethyl-2',4-dimethyl diphenyl ether possesses a dielectric constant of 7.7 and a 1,000 cycle power factor of 012% at 26 C. Thus the ethers disclosed herein are useful as polar dielectric impregnants.

They may be used alone, in admixture with one another and/or in admixture with prior art dielectric impregnants.

As many widely different embodiments of this invention may be made without departing from the spirit and scope hereof, it is to be understood that the invention is not limited to the specific embodiments hereof except as defined in the appended claims.

What we claim is:

A compound conforming to the following general formula:

wherein R represents an aryl group.

2. A compound conforming to the following general formula:

@"Q n C F:

( )n CF:

wherein X represent an alkyl group and nrepresents an integer.

4. 3-trifluoromethyl diphenyl ether. 5. 3-tr1fluoromethy1 phenyl-l-naphthyl ether.

REFERENCES CITED file of this patent: 15 1943,

UNITED STATES PATENTS 6. 3-trifluoromethyl-3'-ethyl diphenyl ether. Number Name Date 2,022,634 Britton et a1 Nov. 26, 1935 MOUSHY MARKARIAN. 2,072,797 Clark et a1 Mar. 2,1937 DAVID B. PEICK. 2,170,782 Clark Aug. 22, 1939 2,199,473 Clark Apr. 23, 1940 OTHER REFERENCES Ser. No. 304,859, Petitcolos (A. P. C.) pub. June 

